I used a Dell M6700 at work which is like a $4000+ laptop. i7 extreme processor and all the fixins (albeit we only can use 32 bit windows so I only have access to 3gb of my avaliable 16GB of RAM) and it locks up when trying to use AutoCADLT and Catia/Solidworks at the same time, but my $400 Asus K Series (i5 processor, 8GB ram) runs Catia, Solidworks, Pro-E, Inventor, and Solid Edge (All programs that take up a shit ton of memory) simultaneously with no problems.